A laser is a thingy that bounces light back and forth until all the rays are perfectly parallel and in the same direction, which basically focuses them.
Unfortunately, wrong in almost every respect.
A LASER is a device that ensures that the majority of the photons emitted are at the same frequency (monochromatic) and are 'in phase'.
(A perfect one would have them all perfectly in phase)
They do this by having one photon stimulate the emission of other photons in-phase and the same colour.
"In Phase" means that the 'peaks' and 'troughs' of the light are exactly together, thus having a much greater effect on the target than if some were 'peak' when others were 'troughs'.
The fact that the light is monochromatic and in phase also lets you do all kinds of other clever stuff, for example reading CDs and DVDs. These actually work by detecting when the distance from disc surface to detector array changes by half-wavelengths, thus causing a massive difference in signal (goes from high to almost zero)
Everything else about LASER light doesn't really matter:
You can always use lenses to focus - or defocus, as in holography, and the majority of LASERs are actually dimmer (less light output) than the tungsten filament lamps you probably use in your house.